Automatic weighing apparatus.



No. 755,034. PATENTBD MAR. 22, 1904. W. NORTHROP. AUTOMATIC WBIGHING APPARATUS.

APPLIUATION FILED OUTA, 1902.

H0 MODEL.

jiq. J

No. 755,034. Patented March 22, 1904.

UNITED STATES PATENT OFFICE.

W'ALTER NORTHROP, OF TORONTO, CANADA, ASSIGNOR TO I-IOIVSON & HOWSON, TRUSTEES, OF PHILADELPHIA, PENNSYLVANIA.

AUTOMATIC WEIGHING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 755,034, dated March 22, 1904:. Application filed October 4, 1902. Serial No. 125,960. (No model.)

To all whom it may concern: justable on the hangers D, as shown in Figs.

Be it known that I, WALTER NORTHROP, of A and 5. The hangers pass through holes 5 the city of Toronto, in the county of York, formed in lugs on the scale-platform and are Province of Ontario, Canada, have invented held as adjusted by means of the set-screws a,

certain new and usefulImprovements in Auto l the hangers being preferably indented, as matic Weighing Apparatus, of which the folshown in Fig. 5, to give a secure grip for the lowing is a specification. points of the set-screws. The delivery-spout 5 5 The object of my invention is to devise is divided by the partitions 6 into a large means for automatically weighing predeterstream-passage E,small stream-passage F, and

i0 mined quantities of a granular material; and a reservoir G, closed by a top 6 with the exit relates particularly to a scale working in ception of a small opening or slot 0 above the conjunction with a delivery-spout provided small stream-passage F. Two valves H H 60 with automatic cut-off apparatus controlled by are connected to a common spindle (Z, pivoted the movement of the scale-beam. in the sides of the delivery spout. These In my scale I employ a large stream and a valves are suitably shaped and proportioned small stream cut oif successively by the fallso that the large stream-passage and the res ing of the scale-beam; and my invention 0011- ervoir are open when the valves are in the 65 sists, essentially, in the means employed for position shown in the drawings, but may be effecting this cut-off without destroying the closed by rotating the spindle (Z through an accuracy of the weighing, substantially as angle of about ninety degrees, as indicated in hereinafter more specifically described and dotted lines in Fig. 3. then definitely claime l. I is a flap hinged at one side of the small 70 Figure 1 is a side elevation of my improved stream-passage F below the opening or slot 0.

apparatus. Fig. 2 is a front sectional eleva- This flap is always substantially vertical, but

tion of the same. Fig. 8 is a front elevation by a slight motion may be brought to one of part of the apparatus. Fig. A is a plan side or the other of the slot 0. hen the flap view with the top 7) removed or broken away is in the position shown in Fig. 2, granular 75 in order to showthe interior construction. material fed to the delivery-spout will pass Fig. 5 is a detail in sectional elevation, showthrough the slot 0 and will be directed by the ing the method ofsupporting the scale-pan. flapI through the small stream-passage F. If,

In the drawings like letters of reference inhowever, the flap be moved to the left-hand dicate corresponding parts in the different figside of the slot, the material coming through 80 ures. the slot will be directed into the reservoir (1?.

In Fig. A, A represents a portion of a scale- As this movement of the flap is not made till beam. As I claim no particular novelty in the valves H H are closed, the material is the scales other than in the method of connectcollected in the reservoir and held until the ing the scale-pan, the scales have not been valves H H are again opened. 8 5 shown complete, only such portions being On one end of the spindle (Z I connect a illustrated as are necessary to the working of short lock-arm J, with which engages one end 40 the apparatus. Hung from the end of the of the trip-lever K. The other end of this scale-beam in an ordinary manner is the scalelever is screw threaded, as shown, and has platform B, and over the scale platform is weights screwed thereon, so that their posi- 9 suitably supported the delivery-spout Q. As tion may be shifted or adjusted as desired, one different heights of bag are used in weighing acting as a lock-nut to the other. The pivot different quantities of material, it is desirable f of the trip-lever is preferably located bethat the distance between the delivery-spout low a line joining its point of engagement and the scale-platform be adjustable. I prowith the lock-lever and the weights. The lug vide for this by making the scale-platform adg is formed on or connected to any suitable part of the scale-beam and has screwed through it a contact-screw '71 adapted to engage the trip-lever, as shown more particularly in Fig. 1. When the scale is light, the pressure of this screw maintains the trip-lever in contact with the lock-arm, as shown in Fig. 1. A short arm 2' is formed on the trip-lever just below the set-screwy, screwed through a suitable lug or projection on the side of the deliveryspout. This serves to limit the movement of the trip-lever when it releases the lock-arm J. On the other end of the spindle (Z I connect a weighted arm L, which when the valves H H are open preferably lies a little past the center, as shown in Fig. l. A spring M is connected to the lock-arm J at the other side of the center and at its other end to the delivery-spout. This spring serves to start the closing movement of the valves, the completion of the movement being made by the combined action of the gravity of the arm L and the tension of the spring. I find this arrangement preferable to depending entirely on spring action or entirely on gravity.

Z: is the pivot-spindle of the flap I, and to this spindle I connect the L-shaped arm N. The upper part of the arm is screw-tln'eaded and has adjustable weights Zscrewed thereon, one weight acting as a lock-nut for the other. The other branch of the arm is provided with an end 0, pivoted thereon by a rule-joint, so that it will rock freely to the right hand, but will be rigid with the arm when straightened out, as shown in Fig. 2. The side of this end is beveled, as shown, and is adapted to engage the round pin m, formed on or connected to the scale-beam. (See Fig. 3.) Extending out from the lock-arm J is a wire a, which passes beneath the wire 0, connected to the arm N.

The operation of my device is substantially as follows: A bag is placed on the scale-platform B. The weighted arm L is then raised to the position shown in the drawings, causing the valves H H and the flap I to open the large and small stream-passages of the delivcry-spout. The scale-platform being light,the end of the scale-beam to which it is attached is raised, causing the contact-screw /1/ to hold the trip-lever Kin its raised position, as shown in Fig. 1. This lever has of course rocked to pass and engage with the end of the lockarm J, which is suitably rounded to admit of this action. The wire a engaging the wire 0 moves the weighted arm L and causes the flap I to assume the position shown. As soon as suflicientmatcrial has been discharged into the bag on the scale-platform the scale-beam drops slightly, and this allows the trip-lever to disengage the lock-arm J. The valves H H are then rapidly shut, as already described. The wire a falling away from the wire 0 permits the end 0 of the weighted arm N to engage the pinon, as shown in Fig. 3. The small stream-passage is now alone active and continues to sift a small stream of material into the bag until the scale-beam exactly balances, when the end 0 slips over the pin 11/. and the Hap I is moved over by the action of the weights Z to close the entrance of the small streampassage and direct the material which comes through the slot 0 into the reservoir i. The full bag is now removed, an empty one substituted, and the arm L once more raised. The pivot of the end 0, it should be noted, permits the arm N being moved to the left past the pin at when the scale-beam is in its raised position.

The arrangement of the fl ap I and the weighted arm N, with its jointed bevel-sided end 0, is an important feature of my invention. The flap I being almost vertical is with a slight expenditure of power easily moved to one side or the other of the slot 0, and this is an important consideration, aswhen the scalebeam is almost on a balance it has hardly any power available to overcome any resistance in the cut-off mechanism which it is required to operate. The beveled end engaging the side of the pin on enables me to give a slight downward pressure on the scale-beam, which completely overcomes the retarding effect of friction between the end and the pin. If the end of the arm were straight and engaged the side of the pin, the retarding effect of this friction would be very noticeable, resulting in the delivery of more material in the seal epan than was actually required to balance the scale. By means of this beveled end I can put a downward pressure on the scale-beam which will cause the arm N to trip a little before a full weight of material has been delivered. The full weight will be made up by the stream of material between the point of cut-oil and the surface of the material on the pan at the time the cutoff takes place. The sensitiveness of the cutoli may be varied by adjusting the weights Z. The contact-screw [L and the :uljustability of the weights 6 are important in insuring accuracy of weighing, as by moving the contact-screw the cut-elf of the large stream may be varied, so as to come closer to or farther from the end of the operation, as may be desired. The rapidity of the cut-oil after the scale-beam once begins to move depends on the position of the weights 6. \Vhile I prefer to provide all these adjustments, yet it is evident that having once accurately adjusted all the parts they may be scaled, so as to be susceptible of no further change, or with great accuracy of construction the adjustable features might be dispensed with, though it is far preferable to provide the adjustments so that any slight variations in the manufacture of the parts or any change in conditions or in wear may be accurately compensated for.

It is necessary to provide means to arrest the movement of the valves H H when they have arrived at the cut-off position, and I prefer to do this by securing the stop I to the side of the delivery-spout in such a position IIO that it may be engaged at the proper time by the arm L- The stop is of course preferably faced with a soft or elastic material.

The momentum of the material issuing from the spout is an element which will spoil the accuracy of the weighing unless it is destroyed before the falling material reaches the surface of the material in the pan, and I therefore place in the mouth of the spout a series of baflles Q in one or two rows. If two rows be employed, they may break joint with one another, as shown. These baffles destroy the momentum in falling from the top to the bottom of the spout, so that it drops easily onto the top of the previously-discharged material.

hat I claim as my invention is- 1. In automatic weighing apparatus provided with weigh-scales and a delivery-spout, the combination of a horizontally-pivoted valve adapted to close the spout; means tending to turn the valve to close the spout; a lock-arm secured to the pivot of the valve; a pivoted trip-lever adapted to engage the lockarm to hold the valve in its open position and weighted so that normally it tends to release the said lock-arm; the scale-beam adapted when in its raised position to directly engage the trip-lever to hold it in position to engage and lift the lock-arm; means for limiting the movement of the trip-lever; and means for stopping the motion of the valve as it reaches the closed position, substantially as described.

2. In automatic weighing apparatus pro vided with weigh-scales and a delivery-spout, the combination of a horizontally pivoted valve adapted to close the spout; means tending to turn the valve to close the spout; a lock-arm secured to the pivot of the valve; a pivoted trip-lever adapted to engage the lock arm to hold the valve in its open position and weighted so that normally it tends to release the said lock-arm; the scale-beam provided with an adjustable contact-piece adapted when the beam is in its raised position to engage the trip-lever to hold it in position to engage the lock-arm; means for limiting the movement of the trip-lever; and means for stopping the motion of the valve as it reaches the closed position, substantially as described.

3. In automatic weighing apparatus provided with weigh-scales and adelivery-spout, the combination of a horizontally-pivoted valve adapted to close the spout; means tending to turn the valve to close the spout; a lockarm secured to the pivot of the valve; a pivoted trip-lever adapted to engage the lockarm to hold the valve in its open position and adjustably Weighted so that normally it tends to release the said lock-arm; the scale-beam provided with an adjustable contact-piece adapted when the beam is in its raised posi- Y tion to engage the trip-lever to hold it in position to engage the lock-arm; means for limiting the movement of the triplever; and

means for stopping the motion of the valve as it reaches the closed position, substantially as described.

4. In automatic weighing apparatus prodded with weigh-scales and a delivery-spout, the combination of a horizontally-pivoted valve adapted to close the spout; means tending to turn the valve to close the spout; a lock-arm secured to the pivot of the valve; a pivoted trip-lever adapted to engage the lockarm to hold the valve in its open position and adjustably weighted so that normally it tends to release the said lock-arm; the scale-beam provided with an adjustable contactpiece adapted when the beam is in its raised position to engage the trip-lever to hold it in position to engage the lock-arm; adjustable means for limiting the movement of the trip-lever; and means for stopping the motion of the valve as it reaches the closed position, substantially as described.

5. In automatic weighing apparatus provided with weigh-scales and a narrow deliveryspout, the combination of asubstantially vertical pivoted flap adapted by its movements to control the said spout; a weighted arm secured to the pivot of the flap and tending to cause the flap to occupy its cut-off position; an arm secured to the pivot and provided with a beveled end; and the scale-beam having a pin thereon adapted to be engaged by the beveled end of the said arm, substantially as described.

(3. 1n automatic weighing apparatus provided with weigh-scales and a narrow deliveryspout, the combination of a substantially vertical pivoted flap adapted by its movements to control the said spout; an adjustablyweighted arm secured to the pivot of the flap and tending to cause the flap to occupy its cutoff position; an arm secured to the pivot and provided with a beveled end; and the scalebeam having a pin thereon adapted to be engaged by the beveled end of the said arm, substantially as described.

7. In automatic weighing apparatus provided with weigh-scales and a narrow deliveryspout, the combination of a substantially vertical pivoted flap adapted by its movements to control the said spout; a weighted arm secured to the pivot of the flap and tending to cause the flap to occupy its cut-off position; an

arm secured to the pivot and provided with a bevel-sided end connected to the arm by a rule-joint; and the scale-beam having a pin thereon adapted to be engaged by the beveled end of the said arm, substantially as de scribed.

8. In automatic weighing apparatus provided with weigh-scales and a narrow deliveryspout, thecombination of a substantially vertical pivoted flap adapted by its movements to control the said spout; an ad justably-weighted arm secured to the pivot of the flap and tending to cause the flap to occupy its cut-off position; an arm secured to the pivot and provid ed with a bevel-sided end connected to the arm by a rule-joint; and the scale-beam having a pin thereon adapted to be engaged by the beveled end of the said arm, substantially as described.

9. In automatic weighing apparatus a delivery-spout; means for cutting off the flow of material through the said spout; a pivoted arm controlling the said means and having a bevel-sided end; and means normally tending to cause the parts to assume the cut-off position, in combination with weigh-scales, the beam of which continuously engages the beveled side of the end when the beam is up during the last stages of the weighing, and releases it when the beam descends to the position of balance, substantially as described.

10. In automatic weighing apparatus the combination of a delivery-spout; partitions dividing the spout into a large passage-way at one side, a narrow passage-way in the center and a reservoir at one side, having a closed top with an opening therein over the central passage-way; valves pivoted by a common spindle and adapted to open and close the lower ends of the large passage-way and the reservoir; a substantially vertical flap pivoted. so that it may be turned to direct material flowing through the small opening in the top of the reservoir either into the reservoir or into the narrow central passage-way; means nor mally held inoperative for causing the valves and flap to close the passage-ways and the bottom of the reservoir; and a scale-beam adapted, when acted upon by the delivery of a sufficient weight of material, to release successively the said means substantially as described.

11. In automatic weighing apparatus, the combination of a delivery-spout provided with a large stream-passage and a small stream passage; oscillating mechanism for control ling each of said passages; arms connected to and oscillating with the said mechanism; wires connected to the said arms and engaging one another so that the opening of the large stream-passage will simultaneously open the small stream passage-way while the large stream passage-way may be cut off independent of the other; means tending to maintain the oscillating passage-closing mechanism in the closed position; means for normally retaining the said passage-closing mechanism in the open position; and a scale-beam adapted when acted upon by the delivery of a suflicient weight of material to release successively the closing mechanism of the two passages, substantially as described.

12. In automatic weighing apparatus the combination of a delivery-spout; partitions dividing the spout into a large passage-way at one side, a narrow passage-way in the center and a reservoir at one side; valves pivoted by a common spindle and adapted to open and close the lower ends of the large passage-way and the reservoir; a substantially vertical flap pivoted so that it may be turned to direct material flowing through the top of the reservoir either into the reservoir or into the narrow central passage-way; means normally held inoperative for causing the valves and flap to close the passage-ways and the bottom of the reservoir; and a scale-beam adapted, when acted upon by the delivery of a sufficient weight of material, to release successively the said means substantially as described.

13. In automatic weighing apparatus, the combination of a delivery-spout provided with a large stream-passage and a small stream-passage; a scale-beam; means controlled by the scale-beam for closing the large stream-passage; means for cutting off the small streampassage; a pivoted arm controlling the saidv means and having a bevel-sided end, and means normally tending to cause the arm to assume the cut-off position, the scale-beam being adapted during the final stage of the weighing when in its raised position to continuously engage the said beveled end and to release it when it drops, substantially as described.

14:. In automatic weighing apparatus provided with weigh-scales and a delivery-spout, the combination of mechanism controlling the flow from the delivery-spout; a rocking lockarm controlling the said mechanism; means tending to turn the controlling mechanism to the cut-off position; a pivoted trip-lever adapted to engage the lock-armto hold the deliverycontrolling mechanism in its feeding position and weighted so that it tends to release the said lock-arm; and the scale-beam adapted when in its raised position to engage the triplever to hold it in position to engage the lockarm; substantially as described.

15. In automatic weighing apparatus provided withweigh-scales and adelivery-spout, the combination of a deliver -spout provided with two passages for material; mechanisms controlling the flow of said passages; rocking arms controllingsaid mechanisms; wires connected to the said arms and engaging one another so that the moving of one lock-arm to the feeding position simultaneously moves the other to the feed position, while permitting consecutive closing; means tending to retain the said passage-controlling mechanisms in the closed position; means for normally retaining the passage-controlling mechanisms in the feeding position; and a scalebeam adapted when acted upon by the delivery of a suflicient weight of material to release successively the closing mechanism of the two passages; substantially as described.

Toronto, September 27, 1902.

IVALTER NORIHROP.

In presence of J. Enw. MAYBnn, A. J. CoLBoUnNu. 

